Development of Rapid Dispense-Printed Flexible Interdigitated Electrode Modified with rGO-TiO₂ Nanohybrid for Glucose Detection

Abstract

A rapid and facile method in developing a printed electrochemical glucose sensor constructed using flexible interdigitated electrode (IDE) employed with reduced graphene oxide (rGO)-Titanium dioxide (TiO2) is demonstrated. A 2x3 silver (Ag)-based IDE array based on a simulated IDE model, was fabricated via a single-step dispense-printing within less than five minutes, while a rGO-TiO2 nanohybrid and glucose oxidase (GOx) enzyme was coated on the IDE surface simply via drop-casting method. Exceptional reproducibility and repeatability of the printed IDE functionalized with rGO-TiO2/GOx in terms of electrical and mechanical performance were observed. The stability of the sensor was investigated over a week period, in which 6-7% performance degradation was recorded based on resistance measurement in flat state, whereas no further significant loss was noted over the same period in bending state. The IDE sensor was tested using chronoamperometry with varied glucose concentrations up to 30 mM, resulted in a stabilized current after 5 s. The sensitivity plot attained depicted a best linear fit of 0.988 obtained at response time of 60 s, while covering lowest detection at 0.05 mM. The application of this sensor could contribute as an alternative method to develop a reliable and economical glucose sensing wearable for independent monitoring.

Development of Screen-Printed Biodegradable Flexible Organic Electrochemical Transistors Enabled by Poly(3,4-ethylenedioxythiophene) Polystyrene Sulfonate and a Solid-State Chitosan Polymer Electrolyte

“…This makes the device performance susceptible to environmental factors like humidity, temperature, and oxidants, affecting the long-term stability. Additionally, for applications of wearable electronics like glucose detection in tissues or cardiac signal recording on a finger, OECTs need to be flexible to mount on biological surfaces such as skin, tissues, and organs. Aqueous electrolytes currently limit OECTs in these applications as they hinder the ability of the devices to flexibly conform to the uneven and curved surfaces or substrates .…”